Abstract: An object is to improve deposition of silicon on a base portion of a silicon filament. A filament holder (10A) includes a filament holding portion (12A) which has a substantially truncated cone shape. The filament holding portion (12A) has, in a top surface (12a) thereof, a filament insert hole (13A) configured to hold a silicon filament (4A). The angle (0) between the axis and the generatrix of the substantially truncated cone shape is not less than 10 degrees and not more than 30 degrees. The margin width (L) of the filament holding portion (12A) between the outer periphery of the top surface (12a) of the filament holding portion (12A) and an inner wall surface (13a), which is contacted by the silicon filament (4A) of the filament insert hole (13A) is not more than 3 mm at at least one location.

Abstract: An apparatus which measures a thickness of a layer using transverse waves of ultrasonic waves, and includes: a sensor unit having a probe for obliquely transmitting and receiving to and from the surface of a material to be measured having first and second layers with different acoustic impedances in a depth direction: an extractor for extracting, from a wave reception signal representing waves received by the probe, reflected waves from a boundary between the first and the second layers of the material; and a calculator for calculating a distance between the surface of the material and the boundary.

Abstract: A liquid flow meter is connected in series with a vaporizer having a vaporizing function and a flow rate-adjusting function and vaporizing a liquid material supplied through said liquid flow meter to compare a flow rate detected by the liquid flow meter with a set value, whereby controlling a quantity of liquid material introduced into a vaporizing chamber provided in said vaporizer on the basis of this comparison result, and thus a flow rate of vaporized gas can be always stably controlled in high-speed response.

Abstract: A vapor controller capable of reducing a thermal influence upon a liquid material to be vaporized as far as possible and always stably controlling a vaporized gas in flow rate in high-speed response and a vapor controller having a vaporizer capable of improving a purge efficiency are provided.